If constructive criticism is the lifeblood of success, then Victor Oladipo—a candidate for the Naismith and Wooden Awards given annually to the nation's best college basketball player—should have a leg up on the competition. Like last year's Naismith and Wooden winner, Anthony Davis of Kentucky, and several other recent basketball luminaries, Oladipo has someone in his corner who isn't awed by him—or afraid to hammer on his shortcomings.

He has a twin sister.

High-profile basketball players with twin sisters have had a great run in recent years. In addition to Oladipo and Davis, there's Dallas Mavericks forward Shawn Marion, Miami Heat forward Rashard Lewis, Kentucky's Alex Poythress and Gordon Hayward, the Utah Jazz forward whose half-court near-miss against Duke in 2010 would have given Butler its first NCAA basketball championship. Given that the odds of a baby being born into a boy-girl twin set are about 1 in 220, it certainly seems like the number of boys in these pairs who are exceptionally good at basketball is disproportionately high.

ENLARGE

Oladipo with his sister Victoria
Courtesy of Victoria Oladipo

There's little science to lean on, here. Representatives at the American College of Sports Medicine couldn't find any studies on the athletic performance of twin athletes who are members of a male-female set. But male players say they feel the advantage of having a female twin.

For Hayward, the former Butler star, his twin sister Heather helped with motivation. The two played mixed doubles well enough in high school that Gordon once thought tennis was his best shot at a college scholarship. "We were always competitive in everything, and I really think it helped me develop my competitive edge," he said. At the same time, he said he never had to do anything alone because Heather was always there. "That gives you confidence to do things you wouldn't normally do."

Many players say their twin helped keep them grounded, which is especially important in basketball, where standout players tend to be surrounded by sycophants, admirers and solicitous coaches from a young age. "She was very encouraging but she also would tell me when I was doing something wrong," said Poythress, who said he couldn't beat his twin, Alexis, in one-on-one games until middle school. "She's not going to BS you. She'll tell you the truth."

Davis's sister, the 5-foot-8 Antoinette, acknowledged at last year's Final Four that some people were surprised to hear that she and the 6-foot-10 Davis had shared a womb. But she was vital in keeping Anthony organized during his senior year of high school, said Kenneth Borre, who had both students in math class at their Chicago charter school. While Anthony's year filled with practices, interviews and photo shoots, Antoinette tracked his homework and projects while also making "#AD23" signs to wave at his games, Borre said.

The effects of twin teamwork seem to have paid dividends: During Kentucky's run to the 2012 NCAA championship, Davis was lauded for his selflessness—a trait that's not typically associated with freshman basketball mega-stars.

Margaret Gatz, a psychology professor at Southern California who has studied twins, said girls tend to be more conscientious than boys, so a twin sister might foster that trait in her brother, "which would go along with being more dedicated to practicing and improving one's skills."

Nancy Segal, a Cal State Fullerton psychology professor, theorized that because girls mature faster than boys, having a twin sister could provide a second mother and extra encouragement. Segal, a twin herself, said that in athletic careers such as Oladipo's, having a twin sister "might have just put them over the top."

One could argue that Oladipo's physical skill alone is enough to make him the season's best player. Against Ohio State last week, he soared to the rim and swatted a shot so far into the stands it looked like the 4:30 flight to Cincinnati. And despite a bum ankle against Michigan State, Oladipo tipped in the go-ahead shot, extended Indiana's lead with a dunk, rebounded a last-minute miss and sank both free throws to seal the win. Even his mistakes are spectacular: the chief one being a fast-break, alley-oop dunk attempt against Michigan that didn't even go in.

But the physical skills weren't always there: Oladipo was a three-star high school recruit, two ticks below the best. At Indiana, Oladipo just this season, as a junior, became one of the best players on his team.

Victoria has always supported her brother, and their mother, Joan, said their thoughts are so synchronized that they can finish one another's sentences. Victoria talked to Victor via Skype throughout his freshman year while he was living with teammate Will Sheehey (who also has a twin sister). Victoria said she and Victor are equally overprotective of one another. But she also said Victor was spoiled as the only son in a family with three girls. She likes to remind him that she's five minutes older, and doesn't hesitate to critique his play. "A boy can do that, but not from that sincere place like from a female," she said.

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